An electronic paper technique is a new display technique, and currently is widely applied to the electronic readers. The electronic paper techniques mainly use microcup-type and microcapsule-type electrophoretic display techniques, both of which achieve at least bicolor display with electrophoretic liquid.
The configuration of an existing microcup-type electronic display screen is shown in FIG. 7. The display screen comprises a top electrode 61, a bottom electrode 62 and an electrophoretic display functional film 63 located between the top electrode 61 and the bottom electrode 62. The electrophoretic display functional film 63 is constituted with a microcup array 631, electrophoretic liquid 632 contained within each microcup of the microcup array 631, charged colorant particles 633 dispersed in the electrophoretic liquid 632, and a sealing layer 634 for sealing the openings of the microcups. When a voltage is applied between the top electrode 61 and the bottom electrode 62, the colorant particles bearing a same kind of charges within the electrophoretic liquid 632 are acted by an electric field and gather around the side of the top electrode 61 or bottom electrode 62 of the microcups, and therefore the top electrode 61 or bottom electrode 62 exhibits a certain color, thus reaching the effect of displaying an image.
The configuration of the existing microcapsule-type electronic display screen is shown in FIG. 8. The display screen comprises a top electrode 71, a bottom electrode 72, and an electrophoretic display functional film 73 located between the top electrode 71 and the bottom electrode 62. The electrophoretic display functional film 73 is constituted with a plenty of microcapsules 74 closely arranged side by side, and electrophoretic liquid 741 is enclosed within each microcapsule 74, and the charged colorant particles 742 are dispersed in the electrophoretic liquid 741. When a voltage is applied between the top electrode 71 and the bottom electrode 72, the colorant particles bearing a same kind of charges within the electrophoretic liquid 741 are acted by an electric field and gather around the side of the top electrode 71 or bottom electrode 72 of the microcapsules, and therefore the top electrode 71 or bottom electrode 72 exhibits a certain color, thus reaching the effect of displaying an image.
Most of the current handwriting screens are formed by combining a display screen and a touch module, the touch module provides positional information, and the display screen provides display function. On one hand, for such handwriting screens, the costs of the touch module and the display screen are high, and on the other hand, software and hardware integration between the systems of the touch screen and the display screen are needed. Therefore, the manufacture costs are high. Furthermore, the endurance power of such handwriting screens is low since the display screen and the circuitry need standby electric power.